1. Field of the Invention
The present invention relates to a portable label applying system which is equipped with a printer, a cassette for taking up a continuous web of printed labels, and a label applicator adapted to be charged with the cassette and to be manually actuated to peel the labels from their backing paper and to apply them to commodities. More particularly, this invention relates to an automatic label winding and charging device for use with the printer of such a portable label applying system.
2. Description of the Prior Art
The prior art has provided a portable type label applicator for printing on labels that are temporarily adhered in series to a web of backing paper, then peeling printed labels from the backing paper and applying them to articles such as commodities. A label applicator of this type is often referred to as a "hand labeler" and is widely used in supermarkets and the like. This hand labeler is employed mainly for applying labels to the commodities at a counter where the commodities are displayed. However, in recent years bar code labels have come into wide use, and the bar codes cannot be accurately printed by the simple type printing head mounted in an existing hand labeler so that they may fail to be correctly read out by an optical reader.
The printing head for the bar codes is necessarily larger than the printing head for the usual alpha/numeric characters because of their standardized size. As a result, the hand labeler with bar code printing capability is accordingly large-sized and too heavy for easy handling so that it augments the fatigue of its operator.
In addition, the bar codes are required to have check digits because a hand labeler finds it difficult, in size and structure, to include a function that automatically computes the check digits. As a result, the check digits have to be separately computed and set in the printing head, thus adding to operational inconvenience for the hand labeler, in this respect.
In Japanese Patent Laid-Open No. 56-210021 entitled "Portable Label Applying System", filed Dec. 28, 1981, there is disclosed a system in which a label web having its labels adhered to backing paper is printed by a desk type printer. In the letter, the label web having the printed label is wound in a cassette which is used to charge a label applicator that does not have a printer. This desk type system accurately and efficiently prints and applies the bar code labels. However, the label web has to be manually wound in the cassette that is mounted in the printer. This manual winding operation is remarkably troublesome.